ShockTube, error message.
Hi
i am investigating a case by using the shockTube tutorial, (rhoCentralFoam solver). My problem is that i get an error message when i am running the simulation. the simulation starts to run, but after a short time i receive an error message. the problem is that i do not know what it means. An excerpt of the two last iterations and the error message i receive is: diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0 ExecutionTime = 0.12 s ClockTime = 1 s Mean and max Courant Numbers = 0.0993913 0.2 deltaT = 1e05 Time = 0.0001 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rhoUx, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rhoE, Initial residual = 0, Final residual = 0, No Iterations 0 ExecutionTime = 0.13 s ClockTime = 1 s #0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so" #1 Foam::sigFpe::sigFpeHandler(int) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so" #2 in "/lib/libc.so.6" #3 Foam::sqrt(Foam::Field<double>&, Foam::UList<double> const&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so" #4 in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam" #5 in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam" #6 __libc_start_main in "/lib/libc.so.6" #7 in "/opt/openfoam171/applications/bin/linux64GccDPOpt/rhoCentralFoam" Floating point exception I have a fealing that the errouniosity is based on the changes i did to the setFieldsDict file. My setFieldsDict file looks like: defaultFieldValues ( volVectorFieldValue U ( 1000 0 0 ) volScalarFieldValue T 349 volScalarFieldValue p 100000 ); regions ( boxToCell { box ( 0 1 1 ) ( 5 1 1 ) ; fieldValues (volVectorFieldValue U ( 1000 0 0 ) volScalarFieldValue T 349 volScalarFieldValue p 100000 ) ; } ); i will have deeply appreciated if someone could have explained to me what the error message means and what i can do to cope with this problem. Alex 
Hi
I think i know what is the problem. When i check the pressure in time folder 0.001 i eventually get negative pressure. So i guess this has to do with the numerics in the algorithm or so, that it cannot handle it. Alex 
zero residuals
Hi,
Did you solve the problem? I am still getting your error. Even when i use other tutorials of rhoCentralFoam i still get the same error. please help me. Kind Regards, Farshad 
Quote:
Farshad, i think the velocity is too high...if you lower the velocity to 900 m/s it should be able to run... Hope this will work for you :) alex 
may be the problem is from turbulency

Quote:
Ok, could you please specify that a little more ? alex 
I have the same problem.it seems the equations of rho don't solve at all.because rho,rhoUx,rhoUy,rhoUz and rhoe are zero in my run.
I don't whats the cause of the problem. 
Try reducing cfl number and/or time step.

Hi all,
I'm solving the flow in a nozzle and I have the same problem that foamer Quote:
Regards 
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